Nitrogen-containing complex-forming polymers are known. U.S. Pat. No. 3,810,888 describes complex-forming polymers wherein 2,2'-bipyridine- or 1,10-phenanthroline-based complex-forming moieties are linked via an acetal group to the macromolecular polymer chain of a hydroxyl groupcarrying polymer. The complex-forming polymers are the reaction products of a polyvinyl alcohol and 4-(p-formylstyryl)-2,2'-bipyridine or 4-(p-formylstyryl)--1,10-phenanthroline respectively. In the Journal of the American Chemical Society. 97 (12), 3454 (1975), polymeric phenanthrolines are described which are prepared by reacting a chlorosulfonated, highly cross-linked polystyrene resin with 5-amino-o-phenanthroline. These complex-forming polymers have in common with the complex-forming polymers of U.S. Pat. No. 3,810,888 that the complex-forming moiety is linked to the macromolecular polymer chain via a hydrolytically unstable group.
European Patent Application 45,277 discloses complex-forming polymers having pendant bipyridyl groups as complex-forming moieties, wherein the bipyridyl groups are linked directly to the macromolecular polymer chain. The polymers are prepared by polymerizing a 4- or 6-vinyl-2,2'-bipyridine. These complex-forming polymers have a disadvantage in that the complex-forming complex-forming polymers have a disadvantage in that the complex-forming moieties are situated very close to the polymer chain and hence may be inaccessible or insufficiently mobile.
In Inorganic Chemistry, 17 (9), 2345 (1978), polystyryl bipyridines are described. These complex-forming polymers are prepared by lithiating a brominated crosslinked polystyrene and subsequently reacting the lithiated polystyrene with bipyridine. It is reported that just over 50% of the brominated phenyl groups are converted to the corresponding phenylpyridine group. Said process not only has a low yield but moreover may give rise to the formation of multicoupled complex-forming groups.